A trinket is basically the feminine word for a 'tool'. The dictionary definition of a trinket is "cheap, showy jewelry", which is the same way you can describe a girl. A trinket is a girl who's just arm candy. She's hot and she knows it. But often, she doesn't have much else going on for her besides her looks. Usually a ditzy girl, she's the flirt of the party wearing the skimpy clothes catching the attention but for all the wrong reasons.

Trinkets are often easy.

Did you see Tara? She's such a trinket with her fake tan and fake nails, trying to fit in with all the guys. She's just arm candy, nobody would really take her home to meet the parents.

"Did you see what that girl was wearing? She's barely leaving anything to the imagination. Not to mention, she's so ditzy, she didn't even understand the jokes people were saying"
"Yea, she's quite the trinket"

Slang word for a beautiful girl. Typically found in Ballyboden slang, where the term originated. Does not refer to the dictionary definition of trinket where an object is of little value, in fact this slang term means the opposite. A fucking real treat of a girl